import java.util.Scanner;
     //前缀和
    public class Main {
        public static void main(String[] args) {
            Scanner in = new Scanner(System.in);
            // 注意 hasNext 和 hasNextLine 的区别
            //先输入数据
            int n = in.nextInt();
            int q = in.nextInt();
            int[] arr = new int[n + 1];
            for(int i = 1;i <= n; i++) {
                arr[i] = in.nextInt();
            }

            //定义一个前缀和数组
            long[] sumDp = new long[n + 1];
            for(int i = 1;i <= n;i++) {
                sumDp[i] =sumDp[i-1] + arr[i];
            }

            while(q > 0) {
                int l = in.nextInt();
                int r = in.nextInt();
                System.out.println(sumDp[r] - sumDp[l-1]);
                q--;
            }
        }
    }
